Tektronix 1A5 Instruction Manual page 77

Fig. 6-16. Input capacitance adjustment, step 14.
Improperly adjusted; (E) Optimum waveform, steps 14-m and n.
h. ADJUST — C 1 08, Fig. 6-16 (A), for optimum flatness and
squareness at the upper left corner of the square wave. ' /2
mm or less overshoot, rounding or tilt should remain. Fig.
6-16 (B) shows the desired results; Fig. 6-16 (C) and (D) show
improper results.
i. Switch the A Input AC-GND-DC switch to GND.
j. Switch the oscilloscope Triggering Slope to — .
k. Move the 20 pF input RC normalizer and associated
components to the В INPUT connector.
l. Switch the В Input AC-GND-DC switch to DC. Adjust
the POSITION control as necessary to obtain a centered
display.
(A) Adjustment locations; ( B)
(Sweep rate 0.2 ms/cm; vertical sensitivity 20mV/cm).
m. CHECK
left corner of the square wave. ' /2 mm or less aberration.
See Fig. 6-16 (E).
n. ADJUST — C208 for optimum flatness and squareness
at the lower left corner of the square wave. ½ mm or less
overshoot, rounding or tilt should remain. See Fig. 6-16 (E).
o. Switch the В Input AC-GND-DC switch to GND and dis ­
connect the 20 pF normalizer and associated components
from the В INPUT connector.
p. INTERACTION — Check steps 15, 16 and 17.
Calibration — Type 1A5
Optimum waveform, steps 14-g and h;
— Optimum flatness and squareness at the lower
(C ) and (D )
6-17